Bottle labeling adhesive



Patented June 13, 1944 BOTTLE LABELING ADHESIVE John F. COIWil'l and Robert 0. White, Balnbridge, N. Y., assignors to The Borden'Company, New York, N. Y., a corporation of New Jersey N Drawing.

7 Claims.

Th present invention is concerned with the labeling of bottles, and particularly such bottles as are to be contacted with water or ice while labeled. Particularly the invention relates to the employment of a novel adhesive in the labeling of bottles for such beverages as are to be chilled, in the bottles, before and at the timeof serving As examples of such beverages, soft drinks and beer may be mentioned, and as is well known it is customary to place bottles of such beverages in broken ice or ice water for a time of several hours to several days, before serving the same. It sometimes happens that the labels detach themselves from the bottle during this contact With the Water. It sometimes happens that the ice becomes wholly melted and Application September 17,1941, Serial No. 411,250

the resulting water warms up somewhat, sometimes up to about room temperature, while in contact with the labeled bottles. Many of'the previously used adhesives are much less resistant to such warmed water thanto ice water, and labels are particularly subject to detaching from the bottles, under theseconditionsi. e. when the ice has melted and the water warms up.

Heretofore the glues most commonly used for labeling bottles of the kind mentioned (and considered by the bottling trade as the best for the purpose), have been mixtures of animal glue with starch. Such glues work only fairly well on high speed bottle-labeling machines, and while they may offer a fairly good resistance to ice water and crushed ice, their resistance to warmer water is often very poor. As a result, while the labels attached therewith can resist ice water fairly well, there is a great. tendency for the labels to detach themselves from the bottles when the ice gets melted and the water in contact with the labeled bottles warms up substantially. As an example, labels attached with one of the most popular (and regarded by many of the bottlers as being the most satisfactory) glues on the market for this purpose, have been found to withstand ice water fairly well, but to mostly come all the bottles when soaked in water at 70 F. for half an hour;

In accordance with the present invention, we propose a casein glue, or special composition, for such labeling operations.

One object of the present invention accordingly, is to produce a labeling paste which will onerate satisfactorily on high speed. labelingmachines of various types of manufacture, such paste including casein. Another object is to supply a casein labeling paste which does not string or draw out in threads excessively during its application on high speed bottle labelingma chines, thus eliminating unsightly smears and disfigurements upon the resulting label, and/or on the bottle. Another object is to produce a casein labeling paste which will not foul the equipment during the operation of labeling with high speed labeling machines; A further object is to produce a casein labeling paste embodying the features above mentioned plus desired water resistance when the labeled bottles are soaked in water, both ice water and water at or near room temperature. A-still further object is to produce a casein labeling paste which does not require dilution with water or other medium at the point of application. Another object is to produce a casein labeling paste which does not have the disadvantage of partially dissolving or softening when the labeled bottles are kept in cold water, thus'ellminating'the' tendency which sometimes exists for the label when th bottle is removed from'the water, to slide and result in the pasty mass soiling the hands of a person holding the bottle.' Still another object is to produce a casein labeling paste which is very fast setting after the label has been applied to the bottle, thus allowing great speed in handling and packing the labeled bottles without the danger of the labels sliding out of register due to the paste not having properly set. Another object is to produce a casein adhesive of paste-like consistency, which is stable, in that form, for at least several months. Other objects will become apparent during the progress of the following specification.

The labels, of course, are usually made of paper, printed or lithographed. The bottles generally used are inade of glass.

With the present day high speed bottle labeling machines, a very small amount of the paste or adhesive is applied to the labels prior to their being smoothly pressed onto the bottles to be labeled. Such bottles, particularly those used for beverages of many kinds, are generally placed for a considerable time in cold water or iced water prior to being served, in order to properly chillthe beverage. Often such labeled beverage bottles and the like may remain in cold water or ice bath-for several days. Sometimes the ice melts, and the temperature of the bath rises so that the labels maybe soaking in this water bath at practically room temperature for a period of time. It is therefore important that the bottle labelingpaste when applied to alabel and attached to bottles, should possess the property of resisting cold water, ice, and also water of a higher temperature, say for example about room temperature, e. g., to F., for a considerable period (several hours to several days).

Such specifications are difncult to obtain, para liquid or pasty glue remains readily spreadable, 7 after making the said liquid or pasty glue, is

usually called its "working life."

We have discovered that by the preparation of a casein labeling paste of the composition described herein, we are able to almost entirely eliminate the defects referred to above. This casein bottle labeling paste can be applied by. V the various high speed bottle labeling machines tested, without difliculty, with a-minimum ap plication of the paste, without danger or the labels curling at the edgesand, mosti-mportant, the bottles labeled with our casein paste withstand the soaking testboth in ice water and in water at 7080 F., (i. e. ordinaryroom temperature). I ,Our invention embraces a creamy paste adhesive comprising organic amides, water soluble V alkaline solvents of casein and compounds of zinc, as set forth herein. In using the term organic amide herein, we mean to include amides such as urea, formamide, thio-urea, ammonium thio-cyanatefiacetamide and the like. By the term alkaline solvents herein, we mean such water soluble alkaline compounds or saltsof sodium, potassium or ammonium, which (used 35 alone or with organic amides) have a solubilizing action on casein. Under the term zinc compounds"- herein,.we include any f-the .known compounds of zinc,-.and especially zinc-oxide, zinc hydroxide, zinc carbonate, zinc ammoniumchlo- 40 .ride, zinc acetate and the like. Y

r In order to more fully explain the nature of this invention we give herewith variousexamples showing how our preferred. product ,(adhesive) may be made, but we do not limit the scope of this invention to the examples cited, these being offered only by way of illustration. All parts are given by weight.

ExAurLz 1 Parts Acid precipitated casein (air-dry, prefererably ground to 24 mesh) 200 Zinc oxide 11.2 Urea 177.4 Y Ethyl para hydroxy benzoate 2.22 Water 707.0 Tributyl citrate (used as a foam abater) 2.22

I Commercial ammonia water 26 B 6.66

The procedure may be as follows:

Into a. steam or hot ,water jacketed kettle place the cold water, add the casein (which is of good commercial grade), zinc oxide, tributyl citrate and ethyl para hydroxy benzoate. Mix thoroughly for about 10 minutes, then add the urea. mix for minutes and then at once add the ammonia. with continued stirring, heat the mixture to approximately 180 F., and the material is then finished, the casein having been completely dissolved, the action complete and the hot labeling pa te resulting is immediately drawn from the mixing kettle into drums for storage or shipment.

The benzoate is a perservative that is not harmful to the casein. -But we-do not desire to restrict the invention to the use of this preservative.

EXAMPLE 2 Same formula and same method of procedure as in Example 1, with the exception that 177.4 parts 01 ammonium thio-cyanate are substituted for the urea.

EXAMPLE 3 Same as Example 1 with the'exception that 177.4 parts of thio-urea are substituted for the same amount of urea. EXAMPLE 4 Same as Example 1 excepting 177.4 parts of formamide are substituted for the same amount of urea.

EXAMPLE 5 Same as Example 1 except that 11 parts of soda ash are substituted for the 6.66 parts of ammonia in Example 1.

EXAMPLE 6 EXAMPLE 7 Same as Example 1 but substituting. 18 parts of commercial borax in place 01 the ammonia water recommended in Example 1.

EXAMPLE 8 Exams: 9

' Same as Example 1 but substituting 12 parts of tetra sodium pyrophosphate for the ammonia water appearing in'Example 1.

EXAMPLE 10 Same as Example 1 but substituting 10 parts of triethanolamine in place of the 6.66 parts of ammonia water appearing in Example 1.

ExAMPLs 11 Casein 200.0 Zinc oxi 20.0 'Urea 180.0 Ethyl para hydroxy benzoate 2.22 Water 488.0 Tributyl citrate 2.0 26 B. ammonia water 8.0

EXAMPLE 12 Casein 200.0 Zinc oxide 11.2 Urea 177.4 Bentonite 1 30.0 Ethyl para hydroxy benzoate 2.22 Water 707.0 Tributyl citrate 2.22

26 Be. ammonia water 7.0

Exmru: 13'

Casein 200.0- Zinc acetate 11.2 Urea 177.4 Ethyl para hydroxy benzoate 2.22 Water 707.0 Tributyl citrate 2.22

5 26 B.- ammonia water 16.0

Exmrru Casein 200.0 Zinc hydroxide paste) 56.0 Urea 177.4 Ethyl para hydroxy benzoate 2.22 Water 662.2 Tributyl citrate", 2.22 26 B. ammonia water 6.66 EXAMPLE 15 Casein 200.0 Zincammonium chloride I 10.0 Urea 177.4 Ethyl para hydroxy benzoate 2.22 Water 707.0 Tributyl citrate 2.22 26 B. ammonia water 6.66

It will be noted that Example 12 discloses the addition of a small amount of bentonite to the formula. The procedure of preparation is therefore somewhat different than indicated in the other examples and we find a satisfactory method is to proceed as follows:

Of the 707 parts of water indicated in the formula, we take 210 parts to which we add the 30 parts of bentonite. By means of a high speed stirrer or other convenient mixing device, the bentonite is dispersed in this cold water .until the bentonite and water form a perfectly smooth,

uniform paste. Thereafter, this bentonite mixture may be added to the additional 497 parts of water and thoroughly mixed. Thereafter, the procedure is as in Example 1, but the '737parts of the thinned bentonite suspension are added. instead of water alone.

Heretofore, many of the usual casein glues have contained an added alkaline earth base (lime or hydrated lime, magnesium oxide or hydroxide or equivalent). It will be observed that none of the above formulas include such added alkaline earth bases, and in the appended claims, the expression free from added alkaline earth bases is intended to mean freedom from added oxides and hydoxides of calcium, barium, strontium and magnesium. We, are of course aware that according to some of the writers, magnesium is not included in the alkaline earth metals, although many of its cmpounds are much like the corresponding calcium compounds.

Freedom from these alkaline earth bases, is characteristic of all glues prepared in accordance with the present invention, and having the properties as set forth in this specification.

We make no claim herein to any glue that contains added basic alkaline earth compounds. Table No. 1 illustrates the difference in water soaking resistance between the bottle labeling paste made according to this invention and a now popular animal glue-starch combination.

1 Taste 1 Soaking tests on labeled-bottles We find that the casein label paste made according to this invention possesses exceptionally good keeping qualities. Thus this paste will keep for six months or more in a perfectly usable condition when stored in closed containers suchas steel drums, paraflin coated fiber containers, metal pails and the like without the need of refrigerator type storage. 'Any ordinary warehouse is sufilcient for proper storage of this material. The containers may be opened, portions removed, the balance kept over a long period of time-several months-without the product changingin character or losing its desired consistency or water resistant quality. Freezing does not harm the product. However, we find that a bottle labeling paste in friction top cans at ordinary atmospheric temperature (made exactly like Example 1 but 'without including the zinc compound, loses its water resistance or soaking resistance when used as a label paste after approximately 3 weeks. Hence there is some peculiar reaction indicated wherein there is a gradual loss of water resistance to the labeled bottles when material not containing the zinc compound is used. This probably takes placegradually, commencing almost immediately after such a product is made. All tests were made for comparative purposes with and without the zinc compound. Comparisons were made by placing the finished product in glass bottles, sealed tin cans and blackiron metal containers. This shows the zinc compound (even though present only in a small amount) to be essential.

This feature of stability is of great importance to the user of a. bottle labeling paste,'in fact absolutelyessential from the standpoint of labeling bottles on which the labels must remain attached to the bottles when the bottles are soaked in water.

In' the above examples we have mentioned the use of ethyl para hydroxy benzoate, as a preservative; The invention is not restricted to the use of this preservature, since numerous other preservatives for casein can be used, e. g., para chlor meta cresol, sodium orthophenyl phenate, sodium meta chloro phenol, etc., and the amount of the Preservative can be varied between wide limits.

In the examples, we have mentioned tributyl citrate as a foam abating agent. Various other foam abating agents may be substituted, e. g., tributyl phosphate, amyl citrate, pine oil etc. The amount of the 10am abater can be varied over a wide range.

In the above examples, the amount of the amide used is only slightly less than the amount oi the casein. In other examples, larger amounts of the amide, up to more than the amount of the casein can be used. Enough should be used so that, in combination with the alkali or ammonia, etc., the casein will all be dissolved.

The bentonite in this adhesive exercises an important physical function in maintaining the proper consistency of the adhesive at difierent temperatures. This makes it possible to apply the adhesive at various temperatures, e. g., at between 60 F. and F.

We claim:

1. An adhesive paste suitable for labeling bottles, such adhesive comprising water as its largest component, casein, an organic amide in amount less than the casein as the largest component of the casein-dissolving agent, a zinc compound in an amount less than said amide, and an alkaline solvent in an amount that, with said amide, will dissolve the casein, such adhesive Paste. being substantially stable against putrefactive fermentation for at least several months, and having a working life of at leastseveral months, and such adhesive paste giving paper labels attached therewith to glass bottles and dried, the property of resisting the action of ice water and of water at about ordinary'room temperature, for at least several days, and such adhesive paste beingfree from added alkaline earth bases.

2. A composition as in claim 1, together with an organic preservative and a foam abater, both in small amount.

3. 'An adhesiv paste suitable for labeling botties whichcomprises Parts Casein 200 An organic amide about 177 to 180 A zinc compound about 10 to 20 Water about 707 alkali, equivalent to about 6.66 parts or 26 B. ammonia water, such adhesive being of a creamy consistency, such paste being stable for at least I several months, and such paste-being free from added alkaline earth bases.

4. An adhesive paste suitable for labeling bottles, such adhesive comprising water as its largest component, casein, an organic amide, a zinc compound in an amount less than said amide, and an alkaline solvent in a amout that, with said amide, will dissolve the casein, the amount of the said amide being several times more than the amount of said alkaline solvent, such adhesive paste being substantially tabl'e' against putrefactive fermentation for at least several months, and having a working life of. at least several months; and such adhesive paste giving paper labels attached therewith to glass bottles and dried, the property of resisting the action of ice water and of water at about ordinary room temperature, for at least several days, and such adhesive paste being free from added alkaline earth bases.

5. A compositionas in claim 1, also containing bentonite.

6. A stable adhesive paste suitable for labeling bottles, such adhesive comprising water as its largest component, casein, an organic amide in amount not considerably less than A; of the amount of said casein, a zinc compound in an amount which is onlya minor fraction of the amount of said amide, and an alkaline solvent in an amount that, with said amide, will dissolve the casein, such adhesive paste being substantially stable against putrefactive fermentation for at least several months, and having a working life of at least several months, and such adhesive paste giving paper labels attached therewith to glass bottles and dried, the property of resisting the action of ice water and of water at about ordinary room temperature, for at least several days, and such adhesive paste being free from added alkaline earth bases.

7. An adhesive paste adapted for labeling botties which are to be soaked in ice water for a period up to several days without the removal of the labels therefrom, such adhesive being composed essentially of v Parts Acid precipitated casein 200 An organic amide, as defined about 177 to 180 A zinc compound about 10 to 20 Alkaline casein solvent, equivalent to about 6.66 to 16 parts of ammonia water of 26 B. Water about 488 to 707 such adhesive being of a creamy consistency and being stable for at least several months, and such adhesive paste being free fromadded alkaline earth bases.

JOHN F. CORWIN.

ROBERT C. WHI TE 

